title: Representing randomness in the communication of individualized cancer risk estimates: effects on cancer risk perceptions, worry, and subjective uncertainty about risk.
abstract: OBJECTIVE
  To test the effect of novel representations of randomness on risk perceptions, worry, and subjective uncertainty about individualized colorectal cancer risk estimates.
  
  
  METHODS
  A web-based factorial experiment was conducted, in which 225 adults aged 40 years and older were provided with hypothetical individualized colorectal cancer risk estimates, using 5 different textual and visual representations varying in expressed randomness. Outcome measures were perceived cancer risk, cancer worry, and subjective uncertainty about cancer risk; the moderating effect of dispositional optimism was also examined.
  
  
  RESULTS
  Representational format was significantly associated with subjective uncertainty about cancer risk, but not with perceived cancer risk or worry. A format using software-based animation to express randomness dynamically led to the highest subjective uncertainty, although a static visual non-random format also increased uncertainty. Dispositional optimism moderated this effect; between-format differences in uncertainty were significant only for participants with low optimism.
  
  
  CONCLUSIONS
  Representing randomness in individualized estimates of cancer risk increases subjective uncertainty about risk. A novel dynamic visual format produces the greatest effect, which is moderated by individual differences in optimism.
  
  
  CONCLUSIONS
  Novel representations of randomness may be effective in improving people's understanding of the essential uncertainty pertaining to individualized cancer risk estimates.
authors.affiliation: Center for Outcomes Research and Evaluation, Maine Medical Center, Portland, ME 04105, USA. hanp@mmc.org
authors.forename: Paul K J
authors.initials: PK
authors.lastname: Han
authors.forename: William M P
authors.initials: WM
authors.lastname: Klein
authors.forename: Bill
authors.initials: B
authors.lastname: Killam
authors.forename: Tom
authors.initials: T
authors.lastname: Lehman
authors.forename: Holly
authors.initials: H
authors.lastname: Massett
authors.forename: Andrew N
authors.initials: AN
authors.lastname: Freedman
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001007:Anxiety / Q000523:psychology*; D003142:Communication; D005239:Fear / Q000523:psychology*; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D009369:Neoplasms / Q000523:psychology*; D010465:Perception; D010817:Physician-Patient Relations; D011379:Prognosis; D012306:Risk; D018570:Risk Assessment / Q000379:methods; D013223:Statistics as Topic; D011795:Surveys and Questionnaires; D014342:Truth Disclosure; D035501:Uncertainty